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I won't bag on their tech that was there he seemed to know his stuff, he only can do what he is told to do. I blame the management. It just seemed as if they didn't want to give the time or really give a darn about helping me find the REAL issue they just wanted money from someone they didn't care who. (The owner actually told me this to my face while I was there). They didn't take the time to do a leak down test, they told me they did but the tech confirmed to me in person that he had not done any such test, so he did it while I was there. 81% leakage...
I think the TwinAir kit was their "quick solution".
His YZ450 had the same problems & the Rock River Tech cleaned & greased everything, curing the problem on that bike.
Bruce372 - we encountered that problem also on the 250, I believe JGR makes a hold down kit
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Well we are still down after the knee surgery. Have no idea what the bike will do under race conditions...
I did the harness thing... DID NOT WORK.... Wish you could have shown them this thread.
I have already put my name on a Yellow 16.
I make no bones about this, if I have the same problems I will record every minute of it and put it on youtube and pay as much as it takes for it to "go viral." People work to damn hard for money for a company to treat there consumers this way. I will go buy a Honda or a Kawi and go down in history as a SOB to the blue crowd.
Ya I bought JGR hold down kit, blows my mind they don't come stock on these things. Bigf19, you are not alone I heard Sexton had a water issue at LL as well. At the Millville national there were 3 Yami's in the pits that would not start and oddly enough it was water related... note that all 3 of these bikes were in the show. Only 2 made it to the starting line...
It's simple really. Put a damn sealed wiring harness in it Yamaha! KTM looks to be better and better by the day...
It's not surprising that Yamaha does not give a damn with my 3 month pathetic experience with them. I also have no good things to say about Rock River. Both of them are a crooked operation and don't care about anything but money.
Chucky
Sorry for a long post.
Obviosly there's not many dirt bikes that come through our shop. I've had two new generation dirt bikes and one of them had no valve clearance (a lot of sand in the airbox) and one with a broken killswitch which ran for about a minute then started running ragged.
I've thought about this problem for quite some time. When asking "upwards", no such problem exists.
My bike have too died several times with no obvious reason or connection to each other. I've ridden two hours in the rain with no problems whatsoever. I power wash after every ride and wash it obsessively. I always use compressed air in the spark plug hole and some kind of water repellant spray everywhere else. I've pulled every connector and cleaned and greased. I've ridden about 20-30 hours between the occurences.
First two times I believe this was because of a faulty kill switch because I disconnected it at the track and it ran fine after that. Still do not use one as it's a potential problem source.
One time it bogged for 30 seconds and then stopped. Did not start until about 30 kicks. Then started, ran great for two hours. And probably 20 hours after that,
One time it started running really bad, misfired and bogged. This was because of the plus wire to the ignition coil had come loose.
Ridden a lot of hours and had it happened again today. Hard braking, then just nothing and it stopped. Fired up first kick and ran great the whole day.
It's probably something electrical and this is what I think.
The main algorithms used in engine management systems to calculate the actual air mass is Speed density, Alpha-N and hybrid. Since there's no mass air flow sensor to measure how much air enters the engine, the ECU calculates this (speed density) from sensor input and the ideal gas law from swept volume, temperature and pressure. Alpha-N uses TPS/RPM.
To me, what this all means is that if any of the air temp sensor, air pressure sensor or water temperature sensor would give a false reading due to sensor failure or water, the bike would run badly but not necessary cut out and die completely. And low voltage to fuel pump would bog but not cut out.
This could however happen if you have no spark or the injector closes completely.
*No RPM reading (stator/pickup). No RPM = No spark or injector opening.
*TPS showing 0% throttle = Overrun mode = Injector closing for better engine braking.
*No voltage to ECU.
When this happens and the bike is unable to start. Plug in the Power Tuner and check all sensor readings and especially RPM when you kick it.
That's all I have at the moment.
Good luck to all of you,
Rob
I can attribute some it to water but no all...
Water is not this bikes friend.
I call total BS on Yamaha not knowing this problem exists. To many local bikes to do it in just my small area. We have a local shop that says they have the fix. I can say that I know of 2 bikes that had the problem he "fixed" them and has not had the problem since. I can 100% vouch for that. He will not share his secret, can't say I blame him. If ours does it again I will carry it to him, anything is worth a try. Again, I am still hoping the TPS was our culprit, not willing to bet on it though.
What is sad IMO is that eventually someone is going to get HURT over this. Ours shut down on my boy to many times in the air. God was with him fortunately.
The 2016 is being powdercoated and prepped now. Hoping no problems out of it lol!
The GYTR Tuner shows a code 13. Air pressure Sensor I believe.
I have ruled out bad fuel, spark, and did a leakdown test so were all good mechanically.
Any ideas?
Jason
Jason
You can start your bike with your Power tuner connected and see the sensor input.
Pit Row
Yes you can see the sensor reading while it's running on the GYTR tuner.
Jason
I checked the air pressure tube from sensor to TB for blockage and it had none. The sensor is reading correct pressure for sea level according to the book. I'm getting 29 inHg or 100 Kpa.
I unplugged and cleaned the connection with electrical cleaner then plugged back in and it ran crisp and good so I thought it was a dirty connection. I then applied dielectric grease on plug in and restarted and it was bogging again.
Geesh !!!!
Still showing code 13 on GYTR tuner.
Jason
1SL-85885-01-00 replaces part number 1SL-85885-00-00.
My readings stay the same when it's running but I'm at sea level and it's reading what it says it's suppose to at seal level.
Jason
Jason
To calculate charge density the ecu needs very accurate pressure and temperature readings.
So I replaced the updated TPS and it went back to idling fine but bogging when the throttle is opened. I put the old TPS back on and it idles fine but runs like crap upon throttle opening with either sensor.
I unplugged the Air pressure sensor with the Tuner attached and the reading didn't change which I thought was odd since other sensors like TPS and WT sensor shows a change when unplugged.
So Its still showing a code 13 so I guess I'll replace the APS next.
I doubt it will do any good.
Jason
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